Project Summary/Abstract This proposal requests funds to purchase a Thermo Scientific Orbitrap Fusion Lumos mass spectrometer (Lumos MS) coupled with a Dionex UltiMate 3000 RSLCnano HPLC system, to meet the rising demands for high-performance proteomics instrumentation on the Newark Campus of Rutgers University. This instrument will be installed at the Center for Advanced Proteomics Research (CAPR) at Rutgers-New Jersey Medical School (NJMS). CAPR scientists, already experienced with the Orbitrap technology, will employ the new Lumos MS to conduct largescale bottom-up and top-down proteomics studies for a major user group of 15 NIH-funded investigators, and others. Many of these studies seek to quantify changes of signaling proteins and identify their post-translational modifications (PTMs) within complex mixtures, necessitating the installation of a Lumos MS that can deliver the vital quantitative precision, detection sensitivity and fragmentation flexibility. The Lumos MS has a unique blend of analytical functionalities that eases in-depth quantitative proteomics analyses by providing: (1) high quantification accuracy: MS and MSn scans at high resolutions, up to 500,000 FWHM, to accurately resolve peptides co-eluting from HPLCs in MS1 and isobaric mass tags in MS3; (2) superior sensitivity: speedy data acquisition rates up to 20 Hz in both Orbitrap and linear ion trap MSn analyses; (3) deep proteome coverage: full parallelization and Synchronous Precursor Section for both MS and MSn that increase the number of proteins identified and improve quantitative accuracy when using isobaric mass tags like those in iTRAQ and TMT and (4) complementary fragmentation modes to identify PTMs and proteoforms: high dynamic range ETD significantly increases fragment ion coverage, which balances CID/HCD for the identification of challenging PTMs and middle-down and top-down characterizations of undigested proteoforms. There is no MS with such impeccably coalesced capabilities at any campus of Rutgers University. NIH provision of this shared Lumos MS will empower CAPR to overcome the limitations of the existing instruments and enhance the comprehensive technical competencies to support the NIH-funded researchers at Rutgers and beyond to accomplish their research goals on neuronal signaling pathways, cancer and cardiac dysfunctions.